But Host Home, a new feature that puts all reservation info in one compact command center, is the biggest upgrade. Why? A responsive host makes for a happy guest. Image: Airbnb

The human touch is Airbnb's greatest strength and weakness. At its best, staying in someone else's place is a refreshing alternative to a trip spent in an antiseptic hotel room. At its worst, you're stuck without sheets or towels or the Wi-Fi password and without any concierge to bug about getting them. The key is giving renters and their hosts an easier way to communicate–and that's just what the new app will do. You might assume that driving travelers to the app would be Airbnb's biggest concern, but with this update, according to founder Brian Chesky, that wasn't necessarily the case. "It's actually a bigger deal when our hosts are on mobile. Because it means that suddenly everyone's responsive–way more responsive."

The new feature, Host Home, gives hosts a dedicated space. That itself is a new idea. "In the previous app, hosting and traveling stuff was all kind of in the same space. There was one inbox for our guests and our hosts–it was the same inbox," says Mobile Product Lead Justin Santamaria, who joined Airbnb from Apple earlier this year.

Host Home is designed to pack in all the data hosts might need to stay on top of their reservations and to approve new ones. Open up the "app within an app," as the designers referred to it, and you're greeted with a smiling face–the person currently staying in your spot or the next one slated to. It's an immediate visual reminder that your guest isn't just some anonymous internet stranger but an actual person you're responsible for accommodating. Below that is a "priorities" section, which serves as a to-do list for pending reservations. Tapping an item brings up the relevant information for that request along with your calendar, so you can see if the dates match up.

"One of the things we kept hearing from our hosts was that there were too many steps involved in terms of trying to get the right data about the guest, in terms of trying to figure out whether to accept or not," Santamaria explains. In fact, many hosts were saying that they'd get a notification about a potential guest and go home to their desktop machine to review all the relevant info. The aim was to make mobile the easiest way for hosts to stay on top of their job. Currently, the company says, about a third of reservation requests are handled through the app. They expect Host Home to drive that number significantly higher.

In addition to improving how information is packaged on both the host and guest side, the app has all sorts of smart interface touches that humanize the interaction and encourage that responsiveness. For one, users' profile pictures are packed in at every turn, displayed prominently on individual listing pages and included in the chat. Just like the banner on top of Host Home, it's a constant reminder that you're dealing with a real, regular person–not some random web weirdo. The design of the chat feature is intended to facilitate quick, informal contact, too. Whereas the past version had a top-down, email-like format, the new one looks just like Facebook chat or iMessage, making it easy to shoot a quick question to a host.

The redesign app tackles a tough challenge. Underneath the sharing economy friendliness, Airbnb is still a transaction, and just like you might want to sit down at a desktop machine to book a hotel room or plan a trip, it's easy to see how people might be inclined to do so for finding a room on Airbnb. Same goes for hosts figuring out whose reservations they can accept. With the new app, Airbnb had to figure out how to get people comfortable doing those things on their phones. "I think design is a pretty important solution for that," says Chesky. "When an app feels beautifully considered and designed, it draws people in." And when hosts get drawn in, everyone's happy. "Part of great hospitality is about being incredibly responsive," he says. "The evidence is pretty clear. Unless you're literally home all day, hosts are going to be more responsive when they're using a mobile device."